CRAHI - Centre de Recerca Aplicada en Hidrometeorologiahttp://hdl.handle.net/2117/3856
Fri, 01 Dec 2017 21:09:19 GMT2017-12-01T21:09:19ZIntercomparison of attenuation correction algorithms for single-polarized X-band radarshttp://hdl.handle.net/2117/111288
Intercomparison of attenuation correction algorithms for single-polarized X-band radars
Lengfeld, Katharina; Berenguer Ferrer, Marc; Sempere Torres, Daniel
Attenuation due to liquid water is one of the largest uncertainties in radar observations. The effects of attenuation are generally inversely proportional to the wavelength, i.e. observations from X-band radars are more affected by attenuation than those from C- or S-band systems. On the other hand, X-band radars can measure precipitation fields in higher temporal and spatial resolution and are more mobile and easier to install due to smaller antennas. A first algorithm for attenuation correction in single-polarized systems was proposed by Hitschfeld and Bordan (1954) (HB), but it gets unstable in case of small errors (e.g. in the radar calibration) and strong attenuation. Therefore, methods have been developed that restrict attenuation correction to keep the algorithm stable, using e.g. surface echoes (for space-borne radars) and mountain returns (for ground radars) as a final value (FV), or adjustment of the radar constant (C) or the coefficient a. In the absence of mountain returns, measurements from C- or S-band radars can be used to constrain the correction. All these methods are based on the statistical relation between reflectivity and specific attenuation. Another way to correct for attenuation in X-band radar observations is to use additional information from less attenuated radar systems, e.g. the ratio between X-band and C- or S-band radar measurements. Lengfeld et al. (2016) proposed such a method based isotonic regression of the ratio between X- and C-band radar observations along the radar beam. This study presents a comparison of the original HB algorithm and three algorithms based on the statistical relation between reflectivity and specific attenuation as well as two methods implementing additional information of C-band radar measurements. Their performance in two precipitation events (one mainly convective and the other one stratiform) shows that a restriction of the HB is necessary to avoid instabilities. A comparison with vertically pointing micro rain radars (MRR) reveals good performance of two of the methods based in the statistical k-Z-relation: FV and a. The C algorithm seems to be more sensitive to differences in calibration of the two systems and requires additional information from C- or S-band radars. Furthermore, a study of five months of radar observations examines the long-term performance of each algorithm. From this study conclusions can be drawn that using additional information from less attenuated radar systems lead to best results. The two algorithms that use this additional information eliminate the bias caused by attenuation and preserve the agreement with MRR observations.
Tue, 28 Nov 2017 15:48:45 GMThttp://hdl.handle.net/2117/1112882017-11-28T15:48:45ZLengfeld, KatharinaBerenguer Ferrer, MarcSempere Torres, DanielAttenuation due to liquid water is one of the largest uncertainties in radar observations. The effects of attenuation are generally inversely proportional to the wavelength, i.e. observations from X-band radars are more affected by attenuation than those from C- or S-band systems. On the other hand, X-band radars can measure precipitation fields in higher temporal and spatial resolution and are more mobile and easier to install due to smaller antennas. A first algorithm for attenuation correction in single-polarized systems was proposed by Hitschfeld and Bordan (1954) (HB), but it gets unstable in case of small errors (e.g. in the radar calibration) and strong attenuation. Therefore, methods have been developed that restrict attenuation correction to keep the algorithm stable, using e.g. surface echoes (for space-borne radars) and mountain returns (for ground radars) as a final value (FV), or adjustment of the radar constant (C) or the coefficient a. In the absence of mountain returns, measurements from C- or S-band radars can be used to constrain the correction. All these methods are based on the statistical relation between reflectivity and specific attenuation. Another way to correct for attenuation in X-band radar observations is to use additional information from less attenuated radar systems, e.g. the ratio between X-band and C- or S-band radar measurements. Lengfeld et al. (2016) proposed such a method based isotonic regression of the ratio between X- and C-band radar observations along the radar beam. This study presents a comparison of the original HB algorithm and three algorithms based on the statistical relation between reflectivity and specific attenuation as well as two methods implementing additional information of C-band radar measurements. Their performance in two precipitation events (one mainly convective and the other one stratiform) shows that a restriction of the HB is necessary to avoid instabilities. A comparison with vertically pointing micro rain radars (MRR) reveals good performance of two of the methods based in the statistical k-Z-relation: FV and a. The C algorithm seems to be more sensitive to differences in calibration of the two systems and requires additional information from C- or S-band radars. Furthermore, a study of five months of radar observations examines the long-term performance of each algorithm. From this study conclusions can be drawn that using additional information from less attenuated radar systems lead to best results. The two algorithms that use this additional information eliminate the bias caused by attenuation and preserve the agreement with MRR observations.Scale characterization and correction of diurnal cycle errors in MAPLEhttp://hdl.handle.net/2117/108756
Scale characterization and correction of diurnal cycle errors in MAPLE
Atencia, Aitor; Zawadzki, Isztar; Berenguer Ferrer, Marc
The most widely used technique for nowcasting of quantitative precipitation in operational and research centers is the Lagrangian extrapolation of the latest radar observations. However, this technique has a limited forecast skill because of the assumptionmade on its formulation, such as the fact that the motion vectors do not change and, evenmore important for convective events, neglect any growth or decay in the precipitation field. In this work, the McGill Algorithm for Precipitation Nowcasting by Lagrangian Extrapolation (MAPLE) errors have been computed for 10 yr of radar composite data over the continental United States. The study of these errors shows systematic bias depending on the time of day. This effect is related to the solar cycle, whose heating energy results in an increase in the average rainfall in the afternoon. This external forcing interacts with the atmospheric system, creating local initiation and dissipation of convection depending on orography, land use, cloud coverage, etc. The signal of the diurnal cycle inMAPLEprecipitation forecast has been studied in different locations and spatial scales as a function of lead time in order to recognize where, when, and for which spatial scales the signal is significant. This information has been used in the development of a scaling correction scheme where the mean errors due to the diurnal cycle are adjusted. The results show that the developed methodology improves the forecast for the spatial scales and locations where the diurnal cycle signal is significant.
Tue, 17 Oct 2017 13:44:08 GMThttp://hdl.handle.net/2117/1087562017-10-17T13:44:08ZAtencia, AitorZawadzki, IsztarBerenguer Ferrer, MarcThe most widely used technique for nowcasting of quantitative precipitation in operational and research centers is the Lagrangian extrapolation of the latest radar observations. However, this technique has a limited forecast skill because of the assumptionmade on its formulation, such as the fact that the motion vectors do not change and, evenmore important for convective events, neglect any growth or decay in the precipitation field. In this work, the McGill Algorithm for Precipitation Nowcasting by Lagrangian Extrapolation (MAPLE) errors have been computed for 10 yr of radar composite data over the continental United States. The study of these errors shows systematic bias depending on the time of day. This effect is related to the solar cycle, whose heating energy results in an increase in the average rainfall in the afternoon. This external forcing interacts with the atmospheric system, creating local initiation and dissipation of convection depending on orography, land use, cloud coverage, etc. The signal of the diurnal cycle inMAPLEprecipitation forecast has been studied in different locations and spatial scales as a function of lead time in order to recognize where, when, and for which spatial scales the signal is significant. This information has been used in the development of a scaling correction scheme where the mean errors due to the diurnal cycle are adjusted. The results show that the developed methodology improves the forecast for the spatial scales and locations where the diurnal cycle signal is significant.Comparison of TRMM Radar Rainfall Estimates with NOAA Next Generation QPEhttp://hdl.handle.net/2117/107477
Comparison of TRMM Radar Rainfall Estimates with NOAA Next Generation QPE
Amitai, Eyal; Llort Pavon, Xavier; Sempere Torres, Daniel
Rainfall rate fields based on TRMM spaceborne radar observations are compared to those based on the new NOAA Next-Generation Quantitative Precipitation Estimation (QPE) high-resolution national mosaic product (Q2). These rainfall fields can be considered as radar products with the largest coverage currently available from space and ground-based radar observations. They probably can also be considered as the most advanced radar rainfall rate products covering a large area. How well do these two products agree? While the accumulated rain rates from all overpasses combined differ by less than 10%, a comparison between the satellite and ground radar probability distribution functions (pdfs) of the instantaneous rain rate shows very large discrepancies. In general, systematic anomalies over the continental U.S. in TRMM radar pdfs compared to the ground-radar pdfs can be recognized. The pdfs of the TRMM radar are generally shifted towards lower rain rates. Moreover, double peaks occur more frequently in the Q2 than in the TRMM radar pdf. Initial results from the comparisons between these two advanced products are presented.
(C) Copyright 2009, Meteorological Society of Japan (MSJ)
Wed, 06 Sep 2017 18:31:43 GMThttp://hdl.handle.net/2117/1074772017-09-06T18:31:43ZAmitai, EyalLlort Pavon, XavierSempere Torres, DanielRainfall rate fields based on TRMM spaceborne radar observations are compared to those based on the new NOAA Next-Generation Quantitative Precipitation Estimation (QPE) high-resolution national mosaic product (Q2). These rainfall fields can be considered as radar products with the largest coverage currently available from space and ground-based radar observations. They probably can also be considered as the most advanced radar rainfall rate products covering a large area. How well do these two products agree? While the accumulated rain rates from all overpasses combined differ by less than 10%, a comparison between the satellite and ground radar probability distribution functions (pdfs) of the instantaneous rain rate shows very large discrepancies. In general, systematic anomalies over the continental U.S. in TRMM radar pdfs compared to the ground-radar pdfs can be recognized. The pdfs of the TRMM radar are generally shifted towards lower rain rates. Moreover, double peaks occur more frequently in the Q2 than in the TRMM radar pdf. Initial results from the comparisons between these two advanced products are presented.Sistema de alerta para procesos torrenciales a escala regional combinando mapas de susceptibilidad y datos del radar meteorológicohttp://hdl.handle.net/2117/107108
Sistema de alerta para procesos torrenciales a escala regional combinando mapas de susceptibilidad y datos del radar meteorológico
Hurlimann Ziegler, Marcel; Berenguer Ferrer, Marc; Palau, Rosa M.; Sempere Torres, Daniel
Los procesos torrenciales como las corrientes de derrubios o flujos hiperconcentrados causan frecuentemente daños importantes e incluso muertos en zonas montañosas. Para afrontar este peligro, los sistemas de alerta son una herramienta muy útil en la mitigación de los impactos de estos procesos hidro-morfológicos. El presente estudio ha desarrollado, implementado y validado un sistema de alerta a escala regional que determina en tiempo real el nivel de alerta en cada subcuenca de una zona seleccionada. Los principales datos de entrada son un mapa de susceptibilidad y la situación meteorológica que se obtiene mediante el radar. Mediante la aplicación de la técnica de lógica difusa y funciones de pertenencia, el mapa de susceptibilidad y el campo de lluvia se determina en cada subcuenca una de tres posibles clases, y finalmente con una matriz de alerta se calcula uno de los tres niveles de alerta (baja, media o alta). Los resultados del sistema de alerta y su validación han sido muy positivos y demuestran la gran utilidad de estas herramientas.
Tue, 22 Aug 2017 11:43:38 GMThttp://hdl.handle.net/2117/1071082017-08-22T11:43:38ZHurlimann Ziegler, MarcelBerenguer Ferrer, MarcPalau, Rosa M.Sempere Torres, DanielLos procesos torrenciales como las corrientes de derrubios o flujos hiperconcentrados causan frecuentemente daños importantes e incluso muertos en zonas montañosas. Para afrontar este peligro, los sistemas de alerta son una herramienta muy útil en la mitigación de los impactos de estos procesos hidro-morfológicos. El presente estudio ha desarrollado, implementado y validado un sistema de alerta a escala regional que determina en tiempo real el nivel de alerta en cada subcuenca de una zona seleccionada. Los principales datos de entrada son un mapa de susceptibilidad y la situación meteorológica que se obtiene mediante el radar. Mediante la aplicación de la técnica de lógica difusa y funciones de pertenencia, el mapa de susceptibilidad y el campo de lluvia se determina en cada subcuenca una de tres posibles clases, y finalmente con una matriz de alerta se calcula uno de los tres niveles de alerta (baja, media o alta). Los resultados del sistema de alerta y su validación han sido muy positivos y demuestran la gran utilidad de estas herramientas.Flash flood forecasting based on rainfall thresholdshttp://hdl.handle.net/2117/101419
Flash flood forecasting based on rainfall thresholds
Alfieri, Lorenzo; Berenguer Ferrer, Marc; Knechtl, Valentin; Liechti, Katharina; Sempere Torres, Daniel; Zappa, M
Wed, 22 Feb 2017 19:29:43 GMThttp://hdl.handle.net/2117/1014192017-02-22T19:29:43ZAlfieri, LorenzoBerenguer Ferrer, MarcKnechtl, ValentinLiechti, KatharinaSempere Torres, DanielZappa, MCritical rainfall conditions for the initiation of torrential flows: results from the Rebaixader catchment (Central Pyrenees)http://hdl.handle.net/2117/98171
Critical rainfall conditions for the initiation of torrential flows: results from the Rebaixader catchment (Central Pyrenees)
Abanco Martínez de Arenzana, Claudia; Hurlimann Ziegler, Marcel; Moya Sánchez, José; Berenguer Ferrer, Marc
Torrential flows like debris flows or debris floods are fast movements formed by a mix of water and different amounts of unsorted solid material. They generally occur in steep torrents and pose high risk in mountainous areas. Rainfall is their most common triggering factor and the analysis of the critical rainfall conditions is a fundamental research task. Due to their wide use in warning systems, rainfall thresholds for the triggering of torrential flows are an important outcome of such analysis and are empirically derived using data from past events.
In 2009, a monitoring system was installed in the Rebaixader catchment, Central Pyrenees (Spain). Since then, rainfall data of 25 torrential flows (“TRIG rainfalls”) were recorded, with a 5-min sampling frequency. Other 142 rainfalls that did not trigger torrential flows (“NonTRIG rainfalls”) were also collected and analyzed. The goal of this work was threefold: (i) characterize rainfall episodes in the Rebaixader catchment and compare rainfall data that triggered torrential flows and others that did not; (ii) define and test Intensity–Duration (ID) thresholds using rainfall data measured inside the catchment by with different techniques; (iii) analyze how the criterion used for defining the rainfall duration and the spatial variability of rainfall influences the value obtained for the thresholds.
The statistical analysis of the rainfall characteristics showed that the parameters that discriminate better the TRIG and NonTRIG rainfalls are the rainfall intensities, the mean rainfall and the total rainfall amount. The antecedent rainfall was not significantly different between TRIG and NonTRIG rainfalls, as it can be expected when the source material is very pervious (a sandy glacial soil in the study site). Thresholds were derived from data collected at one rain gauge located inside the catchment. Two different methods were applied to calculate the duration and intensity of rainfall: (i) using total duration, Dtot, and mean intensity, Imean, of the rainfall event, and (ii) using floating durations, D, and intensities, Ifl, based on the maximum values over floating periods of different duration. The resulting thresholds are considerably different (Imean = 6.20 Dtot-0.36 and Ifl_90% = 5.49 D-0.75, respectively) showing a strong dependence on the applied methodology.
On the other hand, the definition of the thresholds is affected by several types of uncertainties. Data from both rain gauges and weather radar were used to analyze the uncertainty associated with the spatial variability of the triggering rainfalls. The analysis indicates that the precipitation recorded by the nearby rain gauges can introduce major uncertainties, especially for convective summer storms. Thus, incorporating radar rainfall can significantly improve the accuracy of the measured triggering rainfall.
Finally, thresholds were also derived according to three different criteria for the definition of the duration of the triggering rainfall: (i) the duration until the peak intensity, (ii) the duration until the end of the rainfall; and, (iii) the duration until the trigger of the torrential flow. An important contribution of this work is the assessment of the threshold relationships obtained using the third definition of duration. Moreover, important differences are observed in the obtained thresholds, showing that ID relationships are significantly dependent on the applied methodology.
Tue, 13 Dec 2016 15:31:52 GMThttp://hdl.handle.net/2117/981712016-12-13T15:31:52ZAbanco Martínez de Arenzana, ClaudiaHurlimann Ziegler, MarcelMoya Sánchez, JoséBerenguer Ferrer, MarcTorrential flows like debris flows or debris floods are fast movements formed by a mix of water and different amounts of unsorted solid material. They generally occur in steep torrents and pose high risk in mountainous areas. Rainfall is their most common triggering factor and the analysis of the critical rainfall conditions is a fundamental research task. Due to their wide use in warning systems, rainfall thresholds for the triggering of torrential flows are an important outcome of such analysis and are empirically derived using data from past events.
In 2009, a monitoring system was installed in the Rebaixader catchment, Central Pyrenees (Spain). Since then, rainfall data of 25 torrential flows (“TRIG rainfalls”) were recorded, with a 5-min sampling frequency. Other 142 rainfalls that did not trigger torrential flows (“NonTRIG rainfalls”) were also collected and analyzed. The goal of this work was threefold: (i) characterize rainfall episodes in the Rebaixader catchment and compare rainfall data that triggered torrential flows and others that did not; (ii) define and test Intensity–Duration (ID) thresholds using rainfall data measured inside the catchment by with different techniques; (iii) analyze how the criterion used for defining the rainfall duration and the spatial variability of rainfall influences the value obtained for the thresholds.
The statistical analysis of the rainfall characteristics showed that the parameters that discriminate better the TRIG and NonTRIG rainfalls are the rainfall intensities, the mean rainfall and the total rainfall amount. The antecedent rainfall was not significantly different between TRIG and NonTRIG rainfalls, as it can be expected when the source material is very pervious (a sandy glacial soil in the study site). Thresholds were derived from data collected at one rain gauge located inside the catchment. Two different methods were applied to calculate the duration and intensity of rainfall: (i) using total duration, Dtot, and mean intensity, Imean, of the rainfall event, and (ii) using floating durations, D, and intensities, Ifl, based on the maximum values over floating periods of different duration. The resulting thresholds are considerably different (Imean = 6.20 Dtot-0.36 and Ifl_90% = 5.49 D-0.75, respectively) showing a strong dependence on the applied methodology.
On the other hand, the definition of the thresholds is affected by several types of uncertainties. Data from both rain gauges and weather radar were used to analyze the uncertainty associated with the spatial variability of the triggering rainfalls. The analysis indicates that the precipitation recorded by the nearby rain gauges can introduce major uncertainties, especially for convective summer storms. Thus, incorporating radar rainfall can significantly improve the accuracy of the measured triggering rainfall.
Finally, thresholds were also derived according to three different criteria for the definition of the duration of the triggering rainfall: (i) the duration until the peak intensity, (ii) the duration until the end of the rainfall; and, (iii) the duration until the trigger of the torrential flow. An important contribution of this work is the assessment of the threshold relationships obtained using the third definition of duration. Moreover, important differences are observed in the obtained thresholds, showing that ID relationships are significantly dependent on the applied methodology.Debris-flow monitoring for the set-up of a warning and alarm system: experiences from the pyreneeshttp://hdl.handle.net/2117/89406
Debris-flow monitoring for the set-up of a warning and alarm system: experiences from the pyrenees
Hurlimann Ziegler, Marcel; Abanco Martínez de Arenzana, Claudia; Moya Sánchez, José; Berenguer Ferrer, Marc; Vilajosana, Ignasi
Debris-flow monitoring sites provide many important inputs on their mechanics and strongly improved the understanding on this hazardous process. Monitoring data are the basis for future early warning systems (EWS) and alarm systems (AS). In this study, results from the Rebaixader monitoring are presented and evaluated for the implementation in an EWS and AS at catchment scale. The key parameters are the rainfall thresholds for the warning and the ground vibration produced by the moving debris flow for the alarm emission. At regional scale, a preliminary EWS for a test area in the Central-Eastern Pyrenees is evaluated. The EWS is based on quantitative precipitation estimates obtained from the weather radars and a simple susceptibility model, which is applied in each basin of the test area. The experiences gathered in the Pyrenees show that the knowledge on initiation and flow behaviour of debris flows has strongly advanced and facilitate the set-up of operational EWS or AS. However, there are still remaining various uncertainties (especially related to the adequate definition of thresholds), which must be evaluated and continuously eliminated.
Tue, 30 Aug 2016 08:51:38 GMThttp://hdl.handle.net/2117/894062016-08-30T08:51:38ZHurlimann Ziegler, MarcelAbanco Martínez de Arenzana, ClaudiaMoya Sánchez, JoséBerenguer Ferrer, MarcVilajosana, IgnasiDebris-flow monitoring sites provide many important inputs on their mechanics and strongly improved the understanding on this hazardous process. Monitoring data are the basis for future early warning systems (EWS) and alarm systems (AS). In this study, results from the Rebaixader monitoring are presented and evaluated for the implementation in an EWS and AS at catchment scale. The key parameters are the rainfall thresholds for the warning and the ground vibration produced by the moving debris flow for the alarm emission. At regional scale, a preliminary EWS for a test area in the Central-Eastern Pyrenees is evaluated. The EWS is based on quantitative precipitation estimates obtained from the weather radars and a simple susceptibility model, which is applied in each basin of the test area. The experiences gathered in the Pyrenees show that the knowledge on initiation and flow behaviour of debris flows has strongly advanced and facilitate the set-up of operational EWS or AS. However, there are still remaining various uncertainties (especially related to the adequate definition of thresholds), which must be evaluated and continuously eliminated.The great Colorado flood of September 2013http://hdl.handle.net/2117/78527
The great Colorado flood of September 2013
Gochis, David; Rutledge, Steven A.; Sempere Torres, Daniel; Steiner, Matthias; Chandrasekar, V.
During the second week of September 2013, a seasonally uncharacteristic weather pattern stalled over the Rocky Mountain Front Range region of northern Colorado bringing with it copious amounts of moisture from the Gulf of Mexico, Caribbean Sea, and the tropical eastern Pacific Ocean. This feed of moisture was funneled toward the east-facing mountain slopes through a series of mesoscale circulation features, resulting in several days of unusually widespread heavy rainfall over steep mountainous terrain. Catastrophic flooding ensued within several Front Range river systems that washed away highways, destroyed towns, isolated communities, necessitated days of airborne evacuations, and resulted in eight fatalities. The impacts from heavy rainfall and flooding were felt over a broad region of northern Colorado leading to 18 counties being designated as federal disaster areas and resulting in damages exceeding $2 billion (U.S. dollars). This study explores the meteorological and hydrological ingredients that led to this extreme event. After providing a basic timeline of events, synoptic and mesoscale circulation features of the event are discussed. Particular focus is placed on documenting how circulation features, embedded within the larger synoptic flow, served to funnel moist inflow into the mountain front driving several days of sustained orographic precipitation. Operational and research networks of polarimetric radar and surface instrumentation were used to evaluate the cloud structures and dominant hydrometeor characteristics. The performance of several quantitative precipitation estimates, quantitative precipitation forecasts, and hydrological forecast products are also analyzed with the intention of identifying what monitoring and prediction tools worked and where further improvements are needed.
Thu, 29 Oct 2015 16:54:37 GMThttp://hdl.handle.net/2117/785272015-10-29T16:54:37ZGochis, DavidRutledge, Steven A.Sempere Torres, DanielSteiner, MatthiasChandrasekar, V.During the second week of September 2013, a seasonally uncharacteristic weather pattern stalled over the Rocky Mountain Front Range region of northern Colorado bringing with it copious amounts of moisture from the Gulf of Mexico, Caribbean Sea, and the tropical eastern Pacific Ocean. This feed of moisture was funneled toward the east-facing mountain slopes through a series of mesoscale circulation features, resulting in several days of unusually widespread heavy rainfall over steep mountainous terrain. Catastrophic flooding ensued within several Front Range river systems that washed away highways, destroyed towns, isolated communities, necessitated days of airborne evacuations, and resulted in eight fatalities. The impacts from heavy rainfall and flooding were felt over a broad region of northern Colorado leading to 18 counties being designated as federal disaster areas and resulting in damages exceeding $2 billion (U.S. dollars). This study explores the meteorological and hydrological ingredients that led to this extreme event. After providing a basic timeline of events, synoptic and mesoscale circulation features of the event are discussed. Particular focus is placed on documenting how circulation features, embedded within the larger synoptic flow, served to funnel moist inflow into the mountain front driving several days of sustained orographic precipitation. Operational and research networks of polarimetric radar and surface instrumentation were used to evaluate the cloud structures and dominant hydrometeor characteristics. The performance of several quantitative precipitation estimates, quantitative precipitation forecasts, and hydrological forecast products are also analyzed with the intention of identifying what monitoring and prediction tools worked and where further improvements are needed.A water availability prediction system for water managementhttp://hdl.handle.net/2117/77092
A water availability prediction system for water management
Llort Pavon, Xavier; Rodríguez, Álvaro; Sancho, David; Sánchez-Diezma Guijarro, Rafael; Cangròs Alonso, Arnau; Muñoz Morillo, Esteban; Berenguer Ferrer, Marc; Sempere Torres, Daniel
In this work we present a Water Availability Prediction System [WAPS] developed and implemented within two EU-FP7 projects: UrbanWater and WatERP. The aim of the WAPS is to provide information for management purposes, and as a source of information for other modules of the Decision Support Systems integrating the project platforms.
General description of the WAPS, including data sources needed, processing algorithms and techniques used, and implementation examples are presented.
Fri, 25 Sep 2015 10:49:32 GMThttp://hdl.handle.net/2117/770922015-09-25T10:49:32ZLlort Pavon, XavierRodríguez, ÁlvaroSancho, DavidSánchez-Diezma Guijarro, RafaelCangròs Alonso, ArnauMuñoz Morillo, EstebanBerenguer Ferrer, MarcSempere Torres, DanielIn this work we present a Water Availability Prediction System [WAPS] developed and implemented within two EU-FP7 projects: UrbanWater and WatERP. The aim of the WAPS is to provide information for management purposes, and as a source of information for other modules of the Decision Support Systems integrating the project platforms.
General description of the WAPS, including data sources needed, processing algorithms and techniques used, and implementation examples are presented.Debris-flow forecasting at regional scale by combining susceptibility mapping and radar rainfallhttp://hdl.handle.net/2117/27127
Debris-flow forecasting at regional scale by combining susceptibility mapping and radar rainfall
Berenguer Ferrer, Marc; Sempere Torres, Daniel; Hurlimann Ziegler, Marcel
This work presents a technique for debris-flow (DF) forecasting able to be used in the framework of DF early warning systems at regional scale. The developed system is applied at subbasin scale and is based on the concepts of fuzzy logic to combine two ingredients: (i) DF subbasin susceptibility assessment based on geomorphological variables and (ii) the magnitude of the rainfall situation as depicted from radar rainfall estimates. The output of the developed technique is a three-class warning (“low”, “moderate” or “high”) in each subbasin when a new radar rainfall map is available.
The developed technique has been applied in a domain in the eastern Pyrenees (Spain) from May to October 2010. The warning level stayed “low” during the entire period in 20 % of the subbasins, while in the most susceptible subbasins the warning level was at least “moderate” for up to 10 days.
Quantitative evaluation of the warning level was possible in a subbasin where debris flows were monitored during the analysis period. The technique was able to identify the three events observed in the catchment (one debris flow and two hyperconcentrated flow events) and produced no false alarm.
Tue, 07 Apr 2015 09:30:27 GMThttp://hdl.handle.net/2117/271272015-04-07T09:30:27ZBerenguer Ferrer, MarcSempere Torres, DanielHurlimann Ziegler, MarcelThis work presents a technique for debris-flow (DF) forecasting able to be used in the framework of DF early warning systems at regional scale. The developed system is applied at subbasin scale and is based on the concepts of fuzzy logic to combine two ingredients: (i) DF subbasin susceptibility assessment based on geomorphological variables and (ii) the magnitude of the rainfall situation as depicted from radar rainfall estimates. The output of the developed technique is a three-class warning (“low”, “moderate” or “high”) in each subbasin when a new radar rainfall map is available.
The developed technique has been applied in a domain in the eastern Pyrenees (Spain) from May to October 2010. The warning level stayed “low” during the entire period in 20 % of the subbasins, while in the most susceptible subbasins the warning level was at least “moderate” for up to 10 days.
Quantitative evaluation of the warning level was possible in a subbasin where debris flows were monitored during the analysis period. The technique was able to identify the three events observed in the catchment (one debris flow and two hyperconcentrated flow events) and produced no false alarm.